The operator of the nuclear power plant at the center of a radiation scare after being disabled by Japan’s March 11 earthquake and tsunami confirmed yesterday that there had been meltdowns of fuel rods at three of its reactors.
Tokyo Electric Power Co (TEPCO) said meltdowns of fuel rods at three reactors at the Fukushima Dai-ichi plant occurred early in the crisis triggered by the earthquake.
The government and outside experts had said previously that fuel rods at three of the plant’s six reactors had likely melted early in the crisis, but the utility, also known as TEPCO, had only confirmed a meltdown at the No. 1 reactor.
TEPCO officials said a review since early this month of data from the plant concluded the same happened to reactors No. 2 and No. 3.
The preliminary finding, which was reported to Japan’s nuclear safety agency, represents part of an initial effort to explain how events at Fukushima spiraled out of control early in the crisis.
Also yesterday, the government appointed Yotaro Hatamura, a Tokyo University professor of engineering who has studied how complex systems and designs fail, to head a committee that will investigate the cause and handling of the nuclear crisis.
The moves came as a team of investigators from the International Atomic Energy Agency began a two-week visit to Japan to prepare a report on the accident to be submitted to the UN agency next month.
Some analysts said the delay in confirming the meltdowns at -Fukushima suggested the utility feared touching off a panic by disclosing the severity of the accident earlier.
“Now people are used to the situation. Nothing is resolved, but normal business has resumed in places like Tokyo,” said Koichi Nakano, a political science professor at Tokyo’s Sophia University.
Nakano said that by confirming the meltdowns now, TEPCO might be hoping the news will have less impact. The word “meltdown” has such a strong connotation that when the situation was more uncertain more people would likely have fled Tokyo, he said.
Engineers are battling to plug radiation leaks and bring the plant 240km northeast of Tokyo under control more than two months after the magnitude 9.0 earthquake and deadly tsunami that devastated a vast swathe of Japan’s northeast coastline and tipped the economy into recession.
The disaster has triggered a drop of more than 80 percent in TEPCO’s share price and forced the company to seek government aid as it faces compensation liabilities that some analysts say could top US$100 billion.
Japanese Minister of Economy, Trade and Industry Banri Kaieda said the government would approve the formation of a committee later yesterday that would make sure TEPCO follows through with restructuring plans.
TEPCO officials said damage to the No. 2 reactor fuel rods had begun three days after the quake, with much of the fuel rods eventually melting and collecting at the bottom of the pressure vessel containing them.
Fuel rods in the No. 3 reactor were damaged by the afternoon of March 13, they said.
The TEPCO officials repeated that the tsunami had disabled power to the reactors and knocked out their cooling capability.
Hidehiko Nishiyama, a spokesman for the government’s Nuclear and Industrial Safety Agency, expressed a similar view.
“We don’t think the quake affected the important parts of the plant, such as its cooling capacity,” Nishiyama told reporters yesterday, although he added there were still some aspects that needed to be clarified by inspecting the site directly.